U.S. patent application number 13/822869 was filed with the patent office on 2013-07-04 for electrical wire.
This patent application is currently assigned to YAZAKI CORPORATION. The applicant listed for this patent is Takayuki Matsuno. Invention is credited to Takayuki Matsuno.
Application Number | 20130168127 13/822869 |
Document ID | / |
Family ID | 45893303 |
Filed Date | 2013-07-04 |
United States Patent
Application |
20130168127 |
Kind Code |
A1 |
Matsuno; Takayuki |
July 4, 2013 |
ELECTRICAL WIRE
Abstract
The present invention provides an electrical wire which includes
a conductor portion comprising a plurality of element wires being
twisted together, and an insulating covering portion disposed over
the conductor portion. Each of element wires is formed of aluminum
or aluminum alloy material, and has a circular cross-section. The
stranding pitch of the element wires is at least three times
greater than a pitch diameter of the conductor portion but no more
than thirty times greater than the pitch diameter of the conductor
portion.
Inventors: |
Matsuno; Takayuki;
(Susono-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Matsuno; Takayuki |
Susono-shi |
|
JP |
|
|
Assignee: |
YAZAKI CORPORATION
Tokyo
JP
|
Family ID: |
45893303 |
Appl. No.: |
13/822869 |
Filed: |
September 29, 2011 |
PCT Filed: |
September 29, 2011 |
PCT NO: |
PCT/JP2011/073026 |
371 Date: |
March 13, 2013 |
Current U.S.
Class: |
174/110R |
Current CPC
Class: |
H01B 7/0009 20130101;
H01B 7/17 20130101; H01B 13/02 20130101; H01B 1/023 20130101 |
Class at
Publication: |
174/110.R |
International
Class: |
H01B 7/17 20060101
H01B007/17 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 1, 2010 |
JP |
2010-224335 |
Claims
1. An electrical wire, comprising: a conductor portion comprising a
plurality of element wires being twisted together, each element
wire being formed of aluminum or aluminum alloy material and having
a circular cross-section; and an insulating covering portion
disposed over the conductor portion, wherein a stranding pitch of
the element wires is at least three times greater than a pitch
diameter of the conductor portion but no more than thirty times
greater than the pitch diameter of the conductor portion.
2. The electrical wire according to claim 1, wherein the stranding
pitch of the element wires is at least three times greater than the
pitch diameter of the conductor portion but no more than twenty
times greater than the pitch diameter of the conductor portion.
3. The electrical wire according to claim 1, wherein the stranding
pitch of the element wires is at least ten times greater than the
pitch diameter of the conductor portion but no more than twenty
times greater than the pitch diameter of the conductor portion.
4. An electrical wire, comprising: a conductor portion comprising a
plurality of element wires being twisted together, each element
wire being formed of aluminum or aluminum alloy material and having
a circular cross-section; and an insulating covering portion
disposed over the conductor portion, wherein a stranding pitch of
the element wires is at least three times greater than an outer
diameter the conductor portion but no more than thirty times
greater than the outer diameter of the conductor portion.
5. The electrical wire according to claim 4, wherein the stranding
pitch of the element wires is at least three times greater than the
outer diameter the conductor portion but no more than twenty times
greater than the outer diameter of the conductor portion.
6. The electrical wire according to claim 4, wherein the stranding
pitch of the element wires is at least five times greater than the
outer diameter the conductor portion but no more than fifteen times
greater than the outer diameter of the conductor portion.
Description
TECHNICAL FIELD
[0001] The present invention relates to an electrical wire
comprising a conductor portion including a plurality of element
wires, each of which is composed of aluminum or aluminum alloy
material.
BACKGROUND ART
[0002] Conventionally, there has been proposed or suggested that
copper or copper alloy element wire is substituted by aluminum or
aluminum alloy element wire in the conductor portion of an
electrical wire so as to decrease the weight of wiring harness to
be disposed in a vehicle. For example, see Japanese Publication of
Patent Application No. 2009-170315A. The electrical wire to which a
terminal fitting is coupled or attached can be mounted to the
wiring harness.
[0003] However, aluminum or aluminum alloy material generally has
less mechanical strength in comparison with copper or copper alloy
material which has been used as element wire material for a
conductor of an electrical wire. Accordingly, in a case where an
electrical wire having a conductor portion composed of aluminum or
aluminum alloy element wire(s) is employed in a wiring harness for
a vehicle, in particular, the door portion of vehicle, the element
wire is prone to break or fracture.
SUMMARY OF THE INVENTION
[0004] It is an objective of the present invention to provide an
electrical wire comprising a conductor portion having a plurality
of element wires each of which is composed of aluminum or aluminum
alloy material, and is prevented from break or fracture even if the
electrical wire is used for a wiring harness to be disposed inside
a vehicle.
[0005] In one aspect the invention relates to such an electrical
wire, comprising, a conductor portion comprising a plurality of
element wires being twisted together, and an insulating covering
portion disposed over the conductor portion, wherein each of the
element wires is formed of aluminum or aluminum alloy material, and
has a circular cross-section, and wherein a stranding pitch of the
element wires is at least three times greater than a pitch diameter
of the conductor portion but no more than thirty times greater than
the pitch diameter of the conductor portion.
[0006] Preferably, the stranding pitch of the element wires may be
at least three times greater than the pitch diameter of the
conductor portion but no more than twenty times greater than the
pitch diameter of the conductor portion.
[0007] More preferably, the stranding pitch of the element wires
may be at least ten times greater than the pitch diameter of the
conductor portion but no more than twenty times greater than the
pitch diameter of the conductor portion.
[0008] In another aspect the invention relates to such an
electrical wire, comprising, a conductor portion comprising a
plurality of element wires being twisted together, and an
insulating covering portion disposed over the conductor portion,
wherein each of the element wires is formed of aluminum or aluminum
alloy material, and has a circular cross-section, and wherein a
stranding pitch of the element wires is at least three times
greater than an outer diameter the conductor portion but no more
than thirty times greater than the outer diameter of the conductor
portion.
[0009] Preferably, the stranding pitch of the element wires may be
at least three times greater than the outer diameter the conductor
portion but no more than twenty times greater than the outer
diameter of the conductor portion.
[0010] More preferably, the stranding pitch of the element wires
may be at least five times greater than the outer diameter the
conductor portion but no more than fifteen times greater than the
outer diameter of the conductor portion.
[0011] Other objects, features, and advantages of the present
invention will become apparent after review of the specification,
claims, and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows a perspective view of a first embodiment of an
electrical wire in accordance with the invention;
[0013] FIG. 2 shows a cross-sectional view of the electrical wire
of FIG. 1 along the line II.
[0014] FIG. 3 shows a stranding pitch of the element wires of a
conductor;
[0015] FIG. 4 shows a perspective view of a second embodiment of an
electrical wire in accordance with the invention;
[0016] FIG. 5 shows a cross-sectional view of the electrical wire
of FIG. 4 along the line V;
[0017] FIG. 6 shows the relationship between the magnification
ratio of the stranding pitch to the pitch diameter of the conductor
portion (as illustrated by a horizontal axis), and the number of
bending until at least one element wire breaks or fractures (as
illustrated by a vertical axis) for the first embodiment of the
electrical wire.
[0018] FIG. 7 shows the relationship between the magnification
ratio of the stranding pitch to the outer diameter of the conductor
portion (as illustrated by a horizontal axis), and the number of
bending until at least one element wire breaks or fractures (as
illustrated by a vertical axis) for the second embodiment of the
electrical wire.
[0019] FIG. 8 illustrates how to repetitively bend the electrical
wire by use of a device such as jigs.
DETAILED DESCRIPTION OF THE INVENTION
[0020] A first embodiment of an electrical wire in accordance with
the present invention will be described with reference to FIGS. 1
to 3 attached thereto. As shown in FIGS. 1 and 2, the first
embodiment of the electrical wire 1 in accordance with the
invention has a conductor portion 3, and an insulating covering
portion 4 disposed over the conductor portion 3.
[0021] The conductor portion 3 is composed of a plurality of
element wires 5. The conductor portion 3 is shown to include 19
element wires therein. Each of the element wires 5 is substantially
formed of aluminum or aluminum alloy material as conductive metal.
In this regard, the element wire 5 may include inevitable or
unavoidable impurities in addition to aluminum or aluminum alloy
material therein.
[0022] The element wire 5 can be obtained by a drawing process in
which a rod-like aluminum or aluminum alloy metallic material can
be passed through the hole of dies (not shown). In other words, the
element wire 5 is never subjected to compression, and is thus
formed having a circular cross-section.
[0023] Moreover, the conductor portion 3 is formed by tying the
plurality of element wires 5 together, and twisting the plurality
of element wires 5 with respect to the shaft center of the
conductor portion 3. In other words, the conductor portion 3 is
formed by twisting the plurality of element wires 5 together.
Accordingly, the element wires 5 spirally wrap around each other so
as to form the conductor portion 3.
[0024] With reference to FIGS. 2 and 3, a stranding pitch A of the
element wires 5 (see FIG. 3) is at least three times greater than
pitch diameter B (also called as "diameter of layer core B") (see
FIG. 2) of the conductor portion 3 but no more than thirty times
greater than the pitch diameter B of the conductor portion 3. In
other words, the element wires 5 of the conductor portion 3 are
spirally twisted such that the stranding pitch A is at least three
times greater than the pitch diameter B of the conductor portion 3
but no more than thirty times greater than the pitch diameter B of
the conductor portion 3. The term "stranding pitch A" as used
herein is defined as a length along the conductor portion 3 needed
to make one complete rotation (360 degree) of the helically applied
or helically laid element wires. The pitch diameter B as used
herein can be determined by subtracting one outer diameter of the
element wire 5 from maximum outer diameter of the conductor portion
3. In other words, the pitch diameter B can be defined by the outer
diameter of circle passing the center shaft of the element wire 5
which is located at the outmost circumference. Moreover, due to the
outer diameter of the element wire 5 itself, it is physically
impossible that the stranding pitch A is less than three times
greater than the pitch diameter B of the conductor portion 3. In
other words, the conductor portion 3 in which the element wires 5
are twisted together is formed such that the stranding pitch A is
at least three times greater than the pitch diameter B of the
conductor portion 3.
[0025] In certain such embodiments, stranding pitch A of the
element wires 5 of the conductor portion 3 is preferably at least
three times greater than the pitch diameter B of the conductor
portion 3 but no more than twenty times greater than the pitch
diameter B of the conductor portion 3. More preferably, the
stranding pitch A of the element wires 5 of the conductor portion 3
is at least ten times greater than the pitch diameter B of the
conductor portion 3 but no more than twenty times greater than the
pitch diameter B of the conductor portion 3.
[0026] The covering portion 4 is formed of insulating synthetic
resin, and is disposed over the conductor portion 3. The covering
portion 4 has approximately annular cross-section. Both the
conductor portion 3 and the covering portion 4 disposed over the
conductor portion 3 constitute the electrical wire 1 being circular
in cross-section. The covering portion 4 is removed from the
electrical wire 1 at the area of the end portion 2 of the
electrical wire 1, and the conductor portion 3 is thus exposed to
outside at the end portion 2 of the electrical wire 1.
[0027] The exposed conductor portion 3 is coupled to, or attached
to a terminal fitting (not shown) at the end portion 2 of the
electrical wire 1. The terminal fitting can be coupled to a
connector housing, and the connector for the end portion 2 is
attached thereby forming a wiring harness to be mounted inside a
vehicle.
[0028] In accordance with such embodiment, the stranding pitch A of
the element wires 5 is at least three times greater than the pitch
diameter B of the conductor portion 3 but no more than thirty times
greater than the pitch diameter B of the conductor portion 3. The
above stranding pitch A is far less than stranding pitch of the
element wires of a conventional electrical wire. As such, the
element wires 5 of the conductor portion 3 are much more tightly
twisted together in comparison with the element wires of the
conductor portion of the conventional electrical wire. As a result,
the surplus length of the element wire(s) 5 constituting the
conductor portion 3 inside the electrical wire 1 is much greater
than that of the element wire(s) of the conductor portion of the
conventional electrical wire.
[0029] For the reason as set forth above, even if the electrical
wire 1 is repeatedly bent, distortion of the element wire 5 due to
the above repetitive bend can be reliably decreased. Therefore, the
element wires 5 formed of aluminum or aluminum alloy material can
be effectively prevented from break or fracture even if they are
employed for a wiring harness to be disposed inside a vehicle.
[0030] Moreover, in a case where the stranding pitch A of the
element wires 5 is at least three times greater than the pitch
diameter B of the conductor portion 3 but no more than twenty times
greater than the pitch diameter B of the conductor portion 3,
distortion of the element wire 5 due to the above repetitive bend
can be reliably decreased. Therefore, the element wires 5 formed of
aluminum or aluminum alloy material can be effectively prevented
from break or fracture even if they are employed for a wiring
harness to be disposed inside a vehicle.
[0031] In addition, in a case where the stranding pitch A of the
element wires 5 is at least ten times greater than the pitch
diameter B of the conductor portion 3 but no more than twenty times
greater than the pitch diameter B of the conductor portion 3,
distortion of the element wire 5 due to the above repetitive bend
can be reliably decreased. Therefore, the element wires 5 formed of
aluminum or aluminum alloy material can be effectively prevented
from break or fracture even if they are used for a wiring harness
to be disposed inside a vehicle.
[0032] With reference to FIGS. 4 and 5, a second embodiment of an
electrical wire 1 in accordance with the present invention will be
described in detail. The same parts, elements and/or pieces as the
first embodiment of the electrical wire will be represented by the
same symbol, and the detailed description for the corresponding
parts, elements and pieces will be omitted.
[0033] In the second embodiment of the electrical wire 1 in
accordance with the present invention, a conductor portion 3 in
which a plurality of element wires 5 is twisted together is
subjected to compression so as to decrease its cross-sectional
area. As a result, the element wires 5 each having an approximately
hexagonal cross-section are formed. In other words, each of the
element wires 5 constituting the conductor portion 3 is formed as a
compressed conductor. Moreover, the compressed conductor as
described herein is obtained by subjecting an element wire or cable
(i.e., a conductor) to compression to decrease its cross-sectional
area. The above compression can be performed by use of dies (not
shown) and etc.
[0034] In the second embodiment of the electrical wire 1, the
stranding pitch A of the element wires 5 is at least three times
greater than an outer diameter C (see FIG. 5) of the conductor
portion 3 but no more than thirty times greater than the outer
diameter C of the conductor portion 3. In other words, the element
wires 5 are twisted such that the stranding pitch A of the element
wires 5 is at least three times greater than the outer diameter C
of the conductor portion but no more than thirty times greater that
the outer diameter C of the conductor portion 3. Moreover, due to
the outer diameter of the element wire 5 itself, it is physically
impossible that the stranding pitch A is less than three times
greater than the outer diameter C of the conductor portion 3. In
other words, the conductor portion 3 in which the element wires 5
are twisted together is formed such that the stranding pitch A is
at least three times greater than the outer diameter C of the
conductor portion 3.
[0035] In certain such embodiments, the stranding pitch A of the
element wires 5 of the conductor portion 3 is preferably at least
three times greater than the outer diameter C of the conductor
portion 3 but no more than twenty times greater than the outer
diameter C of the conductor portion 3. More preferably, the
stranding pitch A of the element wires 5 of the conductor portion 3
is at least five times greater than the outer diameter C of the
conductor portion 3 but no more than fifteen times greater than the
outer diameter C of the conductor portion 3.
[0036] In accordance with the second embodiment of the electrical
wire 1, the stranding pitch A of the element wires 5 is at least
three times greater than the outer diameter C of the conductor
portion 3 but no more than thirty times greater than the outer
diameter C of the conductor portion 3. The above stranding pitch A
is far less than the stranding pitch of the element wires of a
conventional electrical wire. As such, the element wires 5 of the
conductor portion 3 are more tightly twisted together in comparison
with the element wires of the conductor portion of the conventional
electrical wire. As a result, the surplus length of the element
wire(s) 5 constituting the conductor portion 3 inside the
electrical wire 1 is much greater than the surplus length of the
element wire(s) of the conductor portion of the conventional
electrical wire.
[0037] For the reason as set forth above, even if the electrical
wire 1 is repeatedly bent, distortion of the element wire 5 due to
the above repetitive bend can be reliably decreased. Therefore, the
element wires 5 formed of aluminum or aluminum alloy material can
be effectively prevented from break or fracture even if they are
used for a wiring harness to be disposed inside a vehicle.
[0038] Moreover, in a case where the stranding pitch A of the
element wires 5 is at least three times greater than the outer
diameter C of the conductor portion 3 but no more than twenty times
greater than the outer diameter C of the conductor portion 3,
distortion of the element wire 5 due to the repetitive bend can be
reliably decreased. Therefore, the element wires 5 formed of
aluminum or aluminum alloy material can be effectively prevented
from break or fracture even if they are used for a wiring harness
to be disposed inside a vehicle.
[0039] In addition, in a case where the stranding pitch A of the
element wires 5 is at least five times greater than the outer
diameter C of the conductor portion 3, but no more than fifteen
times greater than the outer diameter C of the conductor portion 3,
distortion of the element wire 5 due to the repetitive bend can be
reliably decreased. Therefore, the element wires 5 formed of
aluminum or aluminum alloy material can be effectively prevented
from break or fracture even if they are used for a wiring harness
to be disposed inside a vehicle.
[0040] The inventors prepared electrical wires 1 of varied
stranding pitches A. Subsequently, the electrical wires 1 were
subjected to repetitive bending to determine the number of bending
until at least one element wire 5 breaks or fractures. The results
are shown in FIGS. 6 and 7.
[0041] With reference to FIGS. 6 and 7, a horizontal axis
represents the magnification ratio of the stranding pitch A of the
element wires 5 to the pitch diameter B or the outer diameter C of
the conductor portion 3, and a vertical axis represents the number
of bending until at least one element wire 5 breaks or fractures.
For more detail, FIG. 6 is shown for the first embodiment of the
electrical wire 1 (i.e., the electrical wire 1 having the conductor
portion 3 having the element wires 5 which are not subjected to
compression, and have circular cross-section respectively). FIG. 7
is shown for the second embodiment of the electrical wire 1 (i.e.,
the electrical wire 1 having the conductor portion 3 having the
element wires 5 which are subjected to compression, and thus have
approximately hexagonal cross-section respectively).
[0042] When the electrical wire 1 is subjected to repetitive
bending, one end (i.e., a superior edge) of the electrical wire 1
is fixed to a jig 20, and the other end (i.e., a lower end) of the
electrical wire 1 is coupled to a weight. For more detail, see FIG.
8. The electrical wire 1 is passed between two cylindrical bending
jigs 22. The jig 20 is moved toward the one of the bending jigs 22,
the one end of the electrical wire 1 is then bent along the outer
periphery of the one of the bending jigs 22, the jig 20 is then
moved toward the other bending jig 22, and the one end of the
electrical wire 1 is then bent along the outer periphery of the
other bending jig 22. As such, the electrical wire 1 is
alternately, repeated, and inversely bent with respect to each
other. If the number of bending for the electrical wire 1 is 1000
or above before at least one element wire 5 breaking or fracturing,
the corresponding electrical wire 1 is determined to be suitable
for use in a wiring harness to be disposed in a vehicle.
[0043] In accordance with FIGS. 6 and 7, the electrical wire 1
having the conductor portion 3 with a plurality of the element
wires 5 the stranding pitch A of which is at least three times
greater than the pitch diameter B or the outer diameter C of the
conductor portion 3 but no more than thirty times greater than the
pitch diameter B or the outer diameter C of the conductor portion 3
survived without any break or fracture of element wires 5 after
repetitive bending of 1000 or above (number) was performed on the
electrical wire 1. The results demonstrates that the element wires
5 formed of aluminum or aluminum alloy material so as to constitute
a part of the electrical wire 1 do not have a tendency to break or
fracture even if the electrical wire 1 is employed in a wiring
harness for a vehicle. In other words, the fatigue strength of the
electrical wire 1 is remarkably enhanced. In addition, in
accordance with FIGS. 6 and 7, the electrical wire 1 having the
conductor portion 3 with a plurality of the element wires 5 the
stranding pitch A of which is at least three times greater than the
pitch diameter B or the outer diameter C of the conductor portion 3
but no more than twenty times greater that the pitch diameter B or
the outer diameter C of the conductor portion 3 survived without
any break or fracture of the element wires 5 after repetitive
bending of 1000 or above (number) was performed on the electrical
wire 1. The result demonstrates that the element wires 5 formed of
aluminum or aluminum alloy material so as to constitute a part of
the electrical wire 1 do not have a tendency to break or fracture
even of the electrical wire 1 is employed in a wiring harness for a
vehicle. In other words, the fatigue strength of the electrical
wire 1 is remarkably enhanced.
[0044] In accordance with FIG. 6, in the case of the electrical
wire 1 having the conductor portion 3 with a plurality of the
element wires 5 the stranding pitch A of which is at least ten
times greater than the pitch diameter B of the conductor portion 3
but no more than twenty times greater than the pitch diameter B of
the conductor portion 3, the element wires 5 formed of aluminum or
aluminum alloy material so as to constitute a part of the
electrical wire 1 do not have a tendency to break or fracture even
if the electrical wire 1 is employed in a wiring harness for a
vehicle. In other words, the fatigue strength of the electrical
wire 1 is remarkably enhanced. In addition, in accordance with FIG.
7, in the case of the electrical wire 1 having the conductor
portion 3 with a plurality of the element wires 5 the stranding
pitch A of which is at least five times greater than the outer
diameter C of the conductor portion 3 but no more than fifteen
times greater that the outer diameter C of the conductor portion 3,
the element wires 5 formed of aluminum or aluminum alloy material
so as to constitute a part of the electrical wire 1 do not have a
tendency to be ruptured even of the electrical wire 1 is employed
in a wiring harness for a vehicle. In other words, the fatigue
strength of the electrical wire 1 is remarkably enhanced.
[0045] Other embodiments and uses of the invention will be apparent
to those skilled in the art from consideration from the
specification and practice of the invention disclosed herein. It is
understood that the invention is not limited to the embodiments
and/or examples herein described, but embraces such modified forms
thereof as come within the scope of the following claims.
* * * * *